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While off topic, get yourself a large powerful magnet, find the north face (the one that the N side of the compass needle attracts to), and place the north field over the pain area. Pain should go away in a few minutes for anything besides a busted kneecap or advanced stage toothache. It will also accelerates healing. Just don't use the wrong side, the south field will aggravate the condition (use compass to verify).
Don't ask how it works, it does. ToysRUs used to have a cheap magnetic levitating top toy with a heavy magnetic base with a powerful 4 x 4 magnet you can gut for this. Large speakers are another source of these.
Okay, back on topic.